Trimming out a ssliding glass door that was replaced

I just moved into a house that had the bedroom sliding door replaced, but it was not finished out. The door sits flush to the outside wall so adding out side trim will not be difficult. The problem is the inside. The door sits recessed in to the existing wall and you can see the cut ends of sheet rock and opening. How do I trim it out??? Can some one direct me to the right information or pictures??? I can usually do the work my self if I can see examples. I can not seem to find anything on completing the trim on the inside of the house after a sliding door has been replaced. Thank you for all input.

 

it sounds like you just need to install an extension jamb onto the rough opening / door. Basically you just measure the distance from where the door jamb sits to the surface of your wall, and cut some wood down to that size. One piece on top, one piece on each side. Run it straight with the door, shim it to the RO, then nail it to the rough opening, or to the door jamb itself. Once those jamb pieces are on, then the inside edge of your casing will have something to nail to.